We have a type that contains mac address field. the data is brought using jdbc river
The cause is that when we run a term aggregation on the mac_address field the results looks like the field is broke into indexed keys:
Action:
GET index/type/_search?search_type=count
{
    "aggs" : { 
        "uniqe_macs" : { 
            "terms" : {
              "field" : "mac_address" 
            }
        }
    }
}
Result:
  "aggregations": {
     "uniqe_visitors": {
        "buckets": [
           {
              "key": "00",
              "doc_count": 1608759
           },
           {
              "key": "10",
              "doc_count": 674633
           },
           {
              "key": "18",
              "doc_count": 588591
           },
           {
              "key": "f0",
              "doc_count": 544897
           },
           {
              "key": "60",
              "doc_count": 538841
           },
           {
              "key": "40",
              "doc_count": 529085
           },
           {
              "key": "08",
              "doc_count": 523681
           },
           {
              "key": "d0",
              "doc_count": 515774
           },
           {
              "key": "54",
              "doc_count": 514771
           },
           {
              "key": "04",
              "doc_count": 509629
           }
        ]
     }
    }
What can be done to force elastic to map this field and not to break it into keys?